Methods: Reproductive data were collected from 20 Minnesota and Iowa breeding herds, covering a 7-year period from January 1, 1986–December 31, 1992. Natural mating was used in all herds during the study period. Females bred one, two, or three times during a single estrus were included in the study to compare fertility rates (conception rate, farrowing rate, and adjusted farrowing rate) and lit...

Spring-calving Angus cows (n = 30) were used to evaluate changes in ruminal temperature (RuT) related to parturition and estrus. Cows were synchronized and artificially inseminated with semen from a single sire. Temperature boluses were placed in the rumen at 7.0 ± 0.2 mo of gestation. Boluses were programmed to transmit RuT every 15 min. Cows (BW = 623 ± 44 kg, BCS = 4.9 ± 0.4) calved during 3...

The present study was conducted to obtain information on the effects of amitraz on reproductive and developmental parameters in rats. The test chemical was administered via the drinking water containing 0, 40, 120, and 360 ppm to male rats from 2 weeks before mating to the end of 14-day mating period and to females from 2 weeks before mating, throughout mating, gestation and up to lactational d...

An experiment was replicated over 2 yr to determine the effect of additional RUP and dietary fat from dried distillers grains plus solubles (DDGS; n = 2) or wet corn gluten feed (WCGF; n = 2) before breeding on primiparous cow reproduction and calf production. Over 2 yr, 134 postpartum, primiparous cows (429 ± 5 kg initial BW) were fed 1 of 2 isocaloric, approximately isonitrogenous diets in 1 ...

the objective of the study was to evaluate the uterine histopathological changes in holstein dairy cows, within the range of 90-145 day in milk, with or without clinical history of reproduction system disorders. lactating holstein cows (n =133) with (n=92, 69.17%) or without (n= 41, 30.82%) recorded clinical signs of reproduction diseases were examined for uterine histopathological lesions. the...

The effect of delayed mating on reproductive potential, longevity and oviposition period of female redbanded leafroller, Argyrotaenia velutinana (Walker) and Pandemis leafroller, Pandemis pyrusana Kearfott, was investigated in the laboratory. Virgin female or male moths of each species were held for 1, 2, 4, 6 or 10 days prior to pairing with one-day-old virgin conspecifics of the opposite sex....

many of insects have re-mating behavoiur during their reproductive period. the re-mating phenomenons have been observed in many ladybirds, too. in current study, the change of proportion of male to female (sex ratio) was used in order to changing of possibility and times of re-mating in hippodamia variegata. in previous studies it has been indicated that males make up about 50% of this predator...

the aim of this study was to evaluate the reproductive efficiency of short and long term treatment with progestagens in addition to pregnant mare serum gonadotropin (pmsg) in arabian ewes during the non-breeding season. a total of 56 ewes were divided into three groups: in group i vaginal sponges (60 mg medroxy progesterone acetate; map) were applied and removed after 6 days; in group ii, vagin...

We investigated how queens share parentage (skew) in the Argentine ant, Linepithema humile, a social insect with multiple queens (polygyny). Overall, maternity of 546 male and female sexuals that mated successfully was determined with microsatellites in 26 colonies consisting of two queens and workers. The first main finding was that queens all contributed to sexual production. However, there w...

The purpose of this study was to determine the milk production and reproductive performance dairy cattle in groups different ages at first calving elucidate effect age on interval Indonesian Holstein cattle. observation method use study. Records 80 cows which were born Indonesia had range 23-32 months used as materials. Cows divided into two based (AFC). Group I with 23-27 group II 28-32 months...